package com.chen.filter;


import com.alibaba.fastjson.JSON;
import com.chen.common.BaseContext;
import com.chen.entity.R;
import lombok.extern.slf4j.Slf4j;
import org.springframework.util.AntPathMatcher;

import javax.servlet.*;
import javax.servlet.annotation.WebFilter;
import javax.servlet.http.HttpServletRequest;
import javax.servlet.http.HttpServletResponse;
import java.io.IOException;

/*
 * 检查用户是否登录
 * */
@Slf4j
@WebFilter("/*")
public class LoginCheckFilter implements Filter {

    //路径匹配器，支持通配符
    public static final AntPathMatcher PATH_MATCHER = new AntPathMatcher();

    @Override
    public void doFilter(ServletRequest servletRequest, ServletResponse servletResponse, FilterChain filterChain) throws IOException, ServletException {
        HttpServletRequest request = (HttpServletRequest) servletRequest;
        HttpServletResponse response = (HttpServletResponse) servletResponse;
        /*
         */
        //A. 获取本次请求的URI
        String uri = request.getRequestURI();
        log.info(uri);
        String[] strings = new String[]{
                "/employee/login",
                "/user/login",
                "/user/sendMsg",
                "/employee/logout",
                "/backend/**",
                "/front/**",
                "/doc.html",
                "/webjars/**",
                "/swagger-resources",
                "/v2/api-docs"
        };


        //B. 判断本次请求, 是否需要登录, 才可以访问
        boolean check = check(strings, uri);
        //C. 如果不需要，则直接放行
        if (check) {
            log.info(uri + "不需要拦截");
            filterChain.doFilter(request, response);
            return;
        }
        //D. 判断登录状态，如果已登录，则直接放行

        Long employee = (Long) request.getSession().getAttribute("employee");
        if (employee != null) {
            log.info(uri + "employee已登录");
            BaseContext.setCurrentId(employee);
            filterChain.doFilter(request, response);
            return;
        }

        Long user = (Long) request.getSession().getAttribute("user");
        if (user != null) {
            log.info(uri + "user已登录");
            BaseContext.setCurrentId(user);
            filterChain.doFilter(request, response);
            return;
        }
        //E. 如果未登录, 则返回未登录结果
        log.info(uri + "未登录");
        response.getWriter().write(JSON.toJSONString(R.error("NOTLOGIN")));
    }

    private boolean check(String[] strings, String uri) {
        for (String string : strings) {
            if (PATH_MATCHER.match(string, uri)) {
                return true;
            }
        }
        return false;
    }
}
